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Ceramic Foam Provides Safe Alternative to Asbestos

HAIFA, Israel and NEW YORK, N.Y., May 16, 2001  Israeli
researchers have begun pilot-scale production of a new
high-temperature thermal ceramic insulator that may become a safe and
economical substitute for asbestos and other potentially harmful
ceramic fibers now in use. The new material is a ceramic foam that
contains 94% to 96% air by volume, but can resist temperatures above
1700° C.

It is being developed under the direction of chemical engineering
professor Gideon Grader at the Technion-Israel Institute of Technology
in Haifa. Prof. Grader established a new company, Cellaris, at the
Technions Entrepreneurial Incubator Company to produce the foam.

The devastating lung ailments, including cancer, that can be caused
by asbestos have led to a search for other high-temperature insulating
materials. But the ceramic fibers that have replaced asbestos also
produce needle-shaped dust particles that can be dangerous to the
lungs when inhaled. In contrast, the crushing of Cellaris ceramic
foam produces ordinary dust particles similar in shape to those common
in the environment, and thus do not pose the health hazards associated
with ceramic fibers.

The foam is made of aluminum oxide, a common high-temperature
ceramic, but gets its extraordinary insulating powers from the many
tiny air bubbles within the material. (Air is a very good thermal
insulator, but needs to be trapped, as in a blanket, to be effective.)
The foam can be used not only for thermal insulation, but for a
variety of other applications such as acoustic insulation and
adsorption of environmental pollutants.

"With only four to five percent of the foam's volume taken up by
the ceramic, the material is an effective insulator that can compete
with today's high-end, state-of-the-art ceramic fibers," Prof. Grader
explains. "Its low density can be important in applications where
weight is at a premium. On a weight-for-weight comparison, the foam
can offer safe, cost-effective insulation."

The foam is generated from special crystals that contain the metal
components and all the foaming ingredients. Upon heating, the crystals
form a solution. Within this solution a reaction takes place, forming
polymer chains. After the chains grow sufficiently, the solution
suddenly separates into a pure solvent and the polymer. At this point,
the solvent begins to boil, forming trillions of tiny bubbles that
blow the polymer into a foam, stabilized by the polymer
chains. Subsequent heating to high temperatures leaves behind the
ceramic, metal oxide foam.

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The foam was developed in Prof. Graders laboratory in 1998,
after years of study of porous ceramics. Government support through
the Technion Entrepreneurial Incubator Company and private seed money
set Cellaris in motion in January 1999. With an additional $700,000
investment from private investors, Cellaris started small-scale pilot
production in February 2001. By June 2001, the company expects to
produce enough material to send samples for testing to a variety of
corporations in the United States and Europe that are interested in
the ceramics possible manufacture or use.

Note to editors: To arrange an interview with Prof. Grader, please
call Adar Novak at 212-307-2519 or email her at adar@ats.org.

The Technion-Israel Institute of Technology is Israel's leading
scientific and technological center for applied research and
education. It commands a worldwide reputation for its pioneering work
in computer science, biotechnology, water-resource management,
materials engineering, aerospace and medicine. The majority of the
founders and managers of Israels high-tech companies are Technion
graduates. The Technions 19 faculties and 30 research centers and
institutes in Haifa are home to 13,000 students and 700 faculty
members.

Based in New York City, the American Technion Society (ATS) is the
leading American organization supporting higher education in
Israel. The ATS has raised more than $800 million since its inception
in 1940, more than half of that during the last eight years.

A nationwide membership organization with more than 20,000
supporters and 17 offices around the country, the ATS is driven by the
belief that the economic future of Israel is in high technology and
the future of high technology in Israel is at the Technion. Technion
societies are located in 24 countries around the world.